Development of a Plant-Based Threshold for Tarnished Plant Bug (Hemiptera: Miridae) in Cotton

Abstract

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is an important pest of cotton, Gossypium hirsutum L., in the mid-southern United States. It is exclusively controlled with foliar insecticide applications, and sampling methods and thresholds need to be revisited. The current experiment was designed to establish a plant-based threshold during the flowering period of cotton development. Experiments were conducted in MisSissippi in 2005 and 2006, Arkansas in 2005, and Louisiana in 2005 through 2008. Treatments consisted of various combinations of thresholds based on the percentage of dirty squares that were compared with the current threshold with a drop cloth or automatic weekly applications. Dirty squares were characterized as those with yellow staining on the developing bud resulting from tarnished plant bug excrement. Treatments consisted of 5, 10, 20, and 30% dirty squares. Each plot was sampled weekly, and insecticides were applied when the mean of all replications of a particular treatment reached the designated threshold. At the end of the season, plots were harvested and lint yields were recorded. Differences were observed in the number of applications and yields among the different treatments. The 10% dirty squares threshold resulted in a similar economic return compared with the drop cloth. A threshold of 10% dirty squares resulted in a similar number of insecticide applications, yields, and economic returns compared with that observed with the drop cloth. These results suggest that a threshold of 10% dirty squares could be used to trigger insecticide applications targeting tarnished plant bugs in flowering cotton.

First transgenic trait for control of plant bugs and thrips in cotton

“…Cotton maturity is impacted by several factors, including planting date, varietal maturity, nitrogen rate, irrigation management, and early season pest management of which thrips are the most important . Unlike other regional pests of cotton, thrips are a widespread annual pest throughout much of the Cotton Belt in the USA .…”

“…The most severe losses were in the Delta region, where Lygus cost an average of $64.68 per acre to treat with six insecticide applications . In some areas, growers have spent up to $100 per acre in foliar applications to achieve adequate Lygus control . Most recently, increasing Lygus pressure has also been observed in the southeastern region.…”

Insight into the Salivary Gland Transcriptome of Lygus lineolaris (Palisot de Beauvois)

“…Insecticide resistance and the ability of TPB to enter diapause, which permits insects to overwinter have made TPB a difficult pest to control [ 24 ]. Economic thresholds based on TPB counts from sweeps and drop cloths as well as counts of dirty squares have been established to assist growers in determining whether TPB countermeasures are economically advisable [ 25 – 27 ]. Of interest, the dirty square symptom that develops into the dirty flower , appears to be the manifestation of molecular catabolism caused by TPB feeding.…”

Long‐term risk assessment on noneffective and effective toxic doses of imidacloprid to honeybee workers

“…Currently, a variety of insecticides are available for pest control, including pyrethroids, organophosphates, carbamates and neonicotinoids. More than forty pesticides are currently recommended by extension specialists for the chemical control of row crop insects (Brandon & Robinson, ; Catchot et al, ; Krupke, Obermeyer, & Bledsoe, ), particularly a variety of insects (e.g., tarnished plant bug and stink bugs) on cotton (Catchot et al, ; Gore et al, ).…”